I plan to order a selection of CMOS logic ic's for experimentation. I don't have a specific project in mind, and plan to spend about $25, which looks like it will buy about 50 pieces. What should I buy and how many of each one?

Then just get the rest as required. Buy at least 1 extra for spares.
If you plan on doing much experimentation, then 5 to 10 pieces as spares is good enough for me (depending on price). This way you don't have to wait for parts to come in when you do need them.

Make sure you keep the ICs stored in the anti-static bags that the parts came in. If you live where the humidity can be high (which is just about everywhere), keep all the bags in a tight plastic bag or container with the little bags of silica gel in with the parts.

PS: With the advent of low cost, low pin count MCUs, the need for digital logic chips has been reduced substantially. I would highly recommend learning to program MCUs if you have not yet done so.

I plan to order a selection of CMOS logic ic's for experimentation. I don't have a specific project in mind, and plan to spend about $25, which looks like it will buy about 50 pieces. What should I buy and how many of each one?

You won't of course get the same speed. Like the CD4017 is good for many MHz of speed. If I were to emulate this in software for a RISC MCU running @5MIPS, then you'd be getting a few 100KHz of throughput.

It really depends on what you're looking to do. I just took the shotgun approach when I ordered parts for a project and bought just about one of every CMOS IC the supplier listed on their website, more for those I knew I'd using. You certainly don't need to go that route. I'd order based on what you think you might get into in the near future, project-wise. Here are my recommendations based on the types of projects I've encountered and found interesting:

4013 - D-flip flop, good for a latching toggle switch (T-flip flop) or for use as part of Bill's 1-second clock circuit that I find myself using a lot, the link to which I don't have handy at the moment.

4017 - chaser LED IC, great for a lot of LED projects

4510 and 4511 - good for presettable up or down counters and 7-segment displays

40110 - combines function of 4510 and 4511 onto one IC without the preset function

4060 - Also used as part of Bill's 1-second clock

4066 - analog switch, haven't used this one yet but plan to in the near future, good to use digital logic switch to turn something on or off somewhat like a relay.

4093 - NAND gate Schmitt trigger - excellent for use as a switch debouncer with 0.1uF cap and 10kΩ resistor, can also be used as a standard NAND gate as far as I know

Some basic logic ICs would be good too, some AND, OR, NOR, XOR, inverter, and buffer might be good such as 4001, 4009, 4010, 4070, 4071, 4081, 40106.

Then look into a PICKit 2 w/Low Pin Count Demo Board for $50, MCU Programming + External logic = best of both worlds, EXTREMELY cool projects using a mix of uC and logic over what you could do with logic alone, or a uC alone.

tracecom,
I just took the shotgun approach when I ordered parts for a project and bought just about one of every CMOS IC the supplier listed on their website, more for those I knew I'd using.

Click to expand...

When I finally I had the money for that, I did more or less the same. At that time I was buying on the counter. Later Internet came and things were different.

Make sure you have all the basic gates and combinations. Also make sure you order the CD4094 (serial to parallel converter). I found myself using it many many times. And the 4015 (right now in a just finished design, waiting for its PCB).

The good thing with that family is that your supply (Vdd) can range from 5 to 15 V. Not bad eh?

The idea of replacing some of these chips with a small micro is older than many are aware of. (Look in the very first application notes of Microchip).

Not even worth discussing about them. Have to see yet an application like that.

In fact, what you do, many times, is replacing that functionality by a small piece of code somewhere in your program to provide what the gate could have offered.

Thanks to all who provided input on this. I had no idea how many different 4000 series IC's there were. (Now, I have found there are about 150 different parts.)

I have made a list of everything recommended here and I have ordered a (used) book of 50 CMOS IC projects. When I get that book, I will finish my order list, and between the two sources (AAC and the book) should have a good starter collection.